Method and appratus for improved gas detection

ABSTRACT

The invention relates to a method and apparatus for providing a reactor having a heater, a passage for transporting a reactant, and a chamber containing a gas sample and being coupled to the passage for receiving the reactant and mixing the reactant with the gas sample. The reactor further includes a connector leading from the chamber to the heater for transporting a mixture of the reactant and gas sample, and wherein the heater heats the mixture of the reactant and gas sample.

PRIORITY APPLICATION

[0001] This application is a continuation in part of copending U.S.patent application Ser. No. 09/443,875 for a “Film Type Solid PolymerIonomer Sensor and Sensor Cell” filed on Nov. 19, 1999.

FIELD OF THE INVENTION

[0002] The invention relates to a method and apparatus for efficientlyoxidizing and/or reducing a gas, resulting in an improved gas detectionsystem.

BACKGROUND OF THE INVENTION

[0003] Gas detection, particularly detection of a specific gas componentin a sample of gases, is traditionally achieved by introducing the gassample into a gas detector, which often may be a mass spectrometer orelectrolytic conductivity detector. Other detection systems may includethermal conductivity, flame ionization, and argon detectors.

[0004] Electrolytic conductivity detectors usually provide an electricalsignal that is functionally related to the presence of a selectedcomponent and typically aid in determining properties of electrolytes insolutions. Such devices often include electrode surfaces with acontinuous phase liquid electrolyte in between the electrode surfaces.These detectors generally entail measuring a difference in potential inthe electrolytic material before and after the gas exiting the columnenters the detector and is absorbed by the electrolytic material. If thegas was mixed with a reactant in the reactor, the reactant may also needto be absorbed in the electrolytic material before providing adetectable electrical signal. A possible disadvantage of theconductivity detector is that absorption by the electrolytic materialtakes time, which lengthens the detector's response time. Thedisadvantage may be exacerbated if both the gas and reactant need to beabsorbed. Another possible disadvantage is a limited sensitivity of thedetector. Because gas is normally detected indirectly, where thedifference in potential of the electrolytic material indicates the typeand/or concentration of the gas, there may be a measurement errorbetween the electrolytic material measurement and correlating this tothe concentration of gas.

[0005] A typical conductivity detector is described in U.S. Pat. No.4,440,726 to Coulson and shown in FIG. 1. Typically, an electrolyte,reactant gas, and gas exiting from the column enter the capillary.Electrodes 24 and 28 are normally placed in the electrolyte solution tomeasure the difference in potential.

[0006] Similar to the conductivity detector, the mass spectrometer andother detection systems of gas chromatography have potentially limitingabilities to detect gas with a high degree of sensitivity. As mentionedin U.S. Pat. No. 6,165,251 to Lemieux et al., detection systems ingeneral have insufficient sensitivity to measure amounts of volatiles inthe parts per billion concentration range.

[0007] Some gas components may have difficulty being detected by thedetector, in which case a reactor may be provided to oxidize and/orreduce the gas sample prior to entering the detector. Generally, thereactor heats the gas sample with a reactant to form a detectablecompound. The more completely a gas sample is oxidized and/or reduced,the more likely an accurate concentration of a desired gas component isdetected by the detector. Partially oxidizing or reducing the gassample, and the gas component, may still result in the desired componentbeing detected but may not result in an accurate concentrationdetermination of the desired component. The reactant may be a gas,liquid, or solid and varies according to the desired gas to be detected.Typical reactants include air, hydrogen, and oxygen. A detectablecompound is one that generally provides an electrical signal detectableby the detector.

[0008] Although it facilitates detection for some gases, the traditionalreactor may not enable sufficient detection or efficient oxidationand/or reduction for other gas components. For example, a reactor thatreduces an aromatic compound without oxidation typically has difficultyreacting hydrogen with the desired element, such as sulfur, of thearomatic compound. However, oxidizing the aromatic compound is believedto weaken the outer ring structure of the aromatic compound, which mayfacilitate reduction, or reaction between hydrogen and the desiredcomponent, such as sulfur. Therefore, oxidation and reduction mayprovide a more efficient conversion of the sulfur in the aromaticcompound to a detectable component.

[0009] Therefore, to provide both oxidation and reduction capabilitiesto traditional detection systems, two reactors would typically be used,where one reactor may be designated for reducing the gas and the otherreactor may be designated for oxidizing the gas.

[0010] GB 1,382,640 to Deschamps (“Deschamps”) relates to a method thatmay oxidize a gas sample in the presence of a catalyst to possiblyprovide an efficient conversion of sulfur compounds to sulfur dioxide atrelatively low temperatures. The invention does not typically relate toefficient conversion during oxidation and reduction.

[0011] U.S. Pat. No. 6,309,612 to Balachandran et al. (“Balachandran”)discloses a ceramic membrane reactor which may contact two reactantgases at different pressures. Balachandran discloses that the tworeactant gases may be introduced during o7xidation but the inventiondoes not typically relate to a reactor having the capability to oxidizeand/or reduce a gas.

[0012] U.S. Pat. No. 6,355,150 to Savin-Poncet et al. (“Savin”)discloses a device that may regulate air injected into a reactor foroxidizing hydrogen disulfide to sulfur. However, the invention does nottypically relate to a system that has the capability to oxidize and/orreduce a gas.

[0013] U.S. Pat. No. 3,934,193 to Hall (“Hall”) discloses a conductivitydetector for detecting a gas. Hall includes an invention that may, asshown in FIGS. 8 and 9 and described in col. 8, provide a detector thatis capable of operating in the reductive and oxidative modes. Hall mayalso describe the furnace operating at 820° C. in the reductive mode and840° C. in the oxidative mode with either hydrogen or oxygen as areaction gas. However, Hall appears to operate the furnace in either thereductive mode or the oxidative mode and not both. Hence, Hall does nottypically describe or show a furnace having the capability of reducingand/or oxidizing a gas sample. In fact, Hall represents the traditionalreactor where two reactors may be needed to reduce and oxidize the gassample.

[0014] A possible disadvantage of Deschamps, Balachandran, Savin, andHall is that two reactors are needed to oxidize and reduce a gas.Another possible disadvantage is that these references may require acatalyst for carrying out the oxidation/reduction.

[0015] U.S. Pat. No. 5,985,673 to Bao et al. (“Bao”) appears to relateto a pyrolyzer which may convert sulfur-containing molecules in a gassample to hydrogen sulfide by oxidizing the gas sample with oxygen andthen reducing the gas sample with hydrogen. However, as shown in theprior art represented by FIG. 1, the pyrolyzer may use a gaschromatograph detector, which typically has limited sensitivity, asdescribed above. In addition, Bao typically introduces the two reactantsinto the gas sample without either premixing the reactants orhomogenously mixing the reactants and gas sample, both of which mayenhance detection because the desirous gas component may then bedetectable in any part of the gas sample.

[0016] What is desired, therefore, is an improved reactor thatfacilitates detection of a gas sample. What is also desired is a reactorhaving the ability to efficiently oxidize and/or reduce a gas. Anotherdesire is to provide a detection system having improved sensitivity andreduced response time for detecting a gas component.

SUMMARY OF THE INVENTION

[0017] It is, therefore, an object of the invention to provide a reactorhaving oxidation and/or reduction capabilities for oxidizing and/orreducing a gas sample to facilitate detection.

[0018] It is another object of the invention to provide anelectrochemical gas sensor coupled to the reactor for improvingdetection of a gas component exiting the reactor.

[0019] These and other objects of the invention are achieved by areactor having a heater, a passage for transporting a reactant, and achamber containing a gas sample and being coupled to the passage forreceiving the reactant and mixing the reactant with the gas sample.

[0020] The reactor further includes a connector leading from the chamberto the heater for transporting a mixture of the reactant and gas sample,and wherein the heater heats the mixture of the reactant and gas sample.

[0021] In some embodiments, the reactor may further include a secondpassage coupled to the connector for transporting a second reactant tothe mixture of the reactant and gas sample. The connector may be placedwithin the second passage and coupled to an outlet, where anelectrochemical gas sensor is coupled to the outlet for detecting a gascomponent in the gas sample.

[0022] The electrochemical gas sensor includes a substrate having asubstrate, an electrode deposited on a surface of the substrate, anionomer membrane in contact with the surface and electrode, the ionomermembrane having a first surface and a second surface, and an opening inthe ionomer membrane extending from the first surface to the secondsurface in a location proximate to the electrode, thereby defining apassage for providing diffusion control for the gas.

[0023] In another embodiment, the reactor includes a heater, a firstpassage for transporting a first reactant, a second passage fortransporting a second reactant, a connector containing a gas sample andbeing coupled to the first passage for receiving the first reactant andmixing the first reactant with the gas sample, and where the connectorextending from the first passage through the heater and coupling to thesecond passage for receiving the second reactant and mixing the firstreactant and gas sample with the second reactant.

[0024] The connector is coupled to the second passage on a side of theheater opposite to the side where the connecter is coupled to the firstpassage. The second passage then passes through the heater, whereby thesecond reactant, first reactant, and gas sample are heated by theheater. An electrochemical gas sensor may also be coupled to the secondpassage for detecting a gas component in the gas sample.

[0025] In another aspect of the invention, a method for providing thereactor in accordance with the invention includes the steps of premixingat least two reactant gases together, combining the premix of the atleast two reactant gases with a gas sample, heating the premix and gassample, and detecting a gas component in the gas sample using anelectrochemical gas sensor having a substrate, an electrode deposited ona surface of the substrate, an ionomer membrane in contact with thesurface and electrode, the ionomer membrane having a first surface and asecond surface, and an opening in the ionomer membrane extending fromthe first surface to the second surface in a location proximate to theelectrode, thereby defining a passage for providing diffusion controlfor the gas.

[0026] The method may further include the step of providing a chamberand homogeneously combining the at least two reactant gases and gassample in the chamber. The method may also include the step ofoxidizing/reducing the premix and gas sample.

[0027] In another aspect of the invention, the method for providing thereactor includes the steps of mixing a first reactant gas with a gassample, heating the mixture of the first reactant gas with the gassample prior to adding the second reactant gas, and adding a secondreactant gas to the first reactant gas and gas sample. The method alsoincludes heating the first reactant gas, second reactant gas, and gassample together and detecting a gas component in the gas sample using anelectrochemical gas sensor having a substrate, an electrode deposited ona surface of the substrate, an ionomer membrane in contact with thesurface and electrode, the ionomer membrane having a first surface and asecond surface, and an opening in the ionomer membrane extending fromthe first surface to the second surface in a location proximate to theelectrode, thereby defining a passage for providing diffusion controlfor the gas.

[0028] The method may also include the step of providing a chamber andhomogeneously combining the first reactant gas, second reactant gas, gassample, and combinations thereof in the chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

[0029]FIG. 1 depicts a conductivity detector known in the prior art.

[0030]FIG. 2 depicts a reactor in accordance with the invention.

[0031]FIG. 3 depicts another embodiment of the reactor shown in FIG. 3.

[0032]FIG. 4 depicts another embodiment of the reactor shown in FIG. 3.

[0033]FIG. 5 depicts an electrochemical gas sensor used with any of therectors shown in FIGS. 2-4.

[0034]FIG. 6 depicts a method for providing the reactor.

[0035]FIG. 7 depicts another aspect of a method for providing thereactor.

DETAILED DESCRIPTION OF THE DRAWINGS

[0036]FIG. 2 depicts the reactor 30 in accordance with the invention.Reactor 30 includes a passage 32 for transporting a reactant 34 and achamber 36 for containing a gas sample which in turn contains a gascomponent that is ultimately detected by the invention.

[0037] Passage 32 may originate from a reactant source, such as anoxygen or hydrogen reservoir, that terminates at chamber 36. Reactant 34is typically another gas, such as oxygen or hydrogen, that reacts with agas sample to aid in detecting the desired gas component. Reactant 34should not be limited to gases but may be any compound or element, ineither a solid or liquid state, that facilitates detection of the gascomponent. Moreover, it should be known that reactant 34 may also bemore than one reactant gas, liquid, solid, or combination thereof.

[0038] The gas sample, which terminates and mixes with reactant 34 inchamber 36, may have originated from an outlet of a gas chromatographcolumn. Chamber 36 provides a homogenous mixture of reactant 34, ormultiple reactants 34, and gas sample. It should be understood thatchamber 36 is desirable but not necessary for reactor 30 to properlyoperate. Chamber 36 is any containment system coupled to passage 32 thatpermits reactant 34, or reactants 34, and gas sample to mix together.Chamber 36 need not be air or water tight to function and may be anycontainer of any shape, such as a tube, conduit, another passage,channel, box, and the like.

[0039] Reactor 30 further includes connector 38 coupled to and extendingfrom chamber 36 to heater 42 for transporting the mixture of reactant(s)34 and gas sample. Connector 38 may further extend through heather 42,where reactant(s) 34 and gas sample are heated within connector 38 orconnector 38 may terminate prior to heater 42 and where reactant(s) 34and gas sample are then transported through heater 42 via anotherconduit. Connector 38 and passage 32 both have the same limitations aseach other and may be a tube, conduit, channel, box, and the like.

[0040] Heater 42 is any known or novel heating element for heatingreactant(s) 34 and/or gas sample and is not germane to the invention

[0041] In a further embodiment shown in FIG. 3, reactor 30 may alsoinclude second passage 44 coupled to connector 38 for transporting asecond reactant 46 to the mixture of reactant 34 or reactants 34 and thegas sample. Second passage 44 includes the same limitations as passage32. Second passage 44 may surround outlet 39 of connector 38, as shown,and direct the emissions of connector 38 back through heater 42 towardoutlet 48.

[0042] The definition of coupling, as referenced above describing theconnections between passage 32, chamber 36, and/or second passage 44,means any direct or indirect connection. Hence, as shown in FIG. 3,passage 32 and connector 38 are coupled to chamber 36, even though oneextends to an interior of chamber 38, and second passage 44 is coupledto connector 38, even though there is no contact between them.

[0043] In another embodiment shown in FIG. 4, connector 38 passesthrough heater 42 and couples to second passage 44 on the opposite sideof heater 42 from where connector 38 joins passage 32 or chamber 36.Although not shown in FIG. 4, chamber 36 may be placed between connector38 and passage 32.

[0044] In some instances, it may be desirable for heater 42 to heat allreactants, 34 and 46, together with the gas sample at the same time andtemperature, in which case the embodiment shown in FIG. 2 may bepreferred. In other instances, it may be desirable to separate theoxidation and reduction reactions from one another, in which case theembodiment shown in FIGS. 3 and 4 may be preferred.

[0045] As shown, after the mixture of reactant 34 and gas sample passfrom connector 38 to second passage 44, a second reactant 46 is mixedwith reactant 34 and gas sample. Second reactant 46 may be a reactantthat facilitates reduction, such as hydrogen.

[0046] An advantage of the embodiments shown in FIGS. 3 and 4 over theembodiment shown in FIG. 2 include the ability to separate the oxidationand reduction stages. Separating these stages from one another mayreduce interference and increase sensitivity when detecting someelements. For exemplary purposes, the following formulas govern thedetection of sulfur in a gaseous mixture, such as a hydrocarbon matrixof propylene.

[0047] The oxidation stage involves reactant 34, connector 38, and thegas sample in heater 42

[0048] Where C₃H₆ is the propylene and CH₃ SH is methyl mercaptan, thecompound containing sulfur, where the sulfur is to be detected.

[0049] As equation 1 shows, the propylene reacts with the oxygenintroduced during oxidation to form CO₂ and water. The sulfur compoundreacts with the oxygen to form SO₂, water, and CO₂.

[0050] The reduction stage involves second reactant 46, second passage44, and the gas sample in heater 42.

[0051] SO₂ reacts with the hydrogen introduced during reduction to formH₂S and oxygen and the remaining hydrogen and oxygen react to formwater. H₂S is detected by sensor 52 to indicate the amount of sulfurpresent in the propylene.

[0052] It is understood that equations 1 through 4 depend upontemperature and pressure within reactor 42. For exemplary purposes, thetemperature is 1000° C. and the pressure is 1 atm. However, anytemperature or pressure may be used provided the equations are modifiedaccordingly and that the temperature and pressure are not germane to theinvention. Although sensor 52 may detect SO₂, which would also indicatethe amount of sulfur, empirical or theoretical information shows thatthe sensor is more sensitive to H₂S and, therefore, more easily detectedby sensor 52 and more accurately indicates the amount of sulfur present.

[0053] By way of comparison, in the embodiment shown in FIG. 2,oxidation and reduction occurs simultaneously and results in a loss insensor sensitivity. For the same sulfur compound methyl mercaptan inpropylene, hydrogen reacts with the oxygen of equation 1 to form water.Therefore, not all of the oxygen in equation 1 can be used to convertpropylene to CO₂, which results in the formation of carbon, or C,instead of CO₂. Coke, or carbon, then builds up within reactor 42 and isknown to absorb H₂S. Hence, detecting an accurate amount of sulfur inpropylene H₂S is hindered because part of the H₂S is absorbed andundetectable. In other words, hydrogen may be argued to interfere withthe conversion of propylene to CO₂ in embodiments where the oxidationand reduction stages are not separated. This is more particulardescribed in formula 5.

[0054] In another example of detecting a total amount of sulfur in asulfur compound, such as methyl mercaptan CH₃SH, H₂S may be formed anddetected without a need to oxidize the compound. For example,

[0055] In addition to reducing possible interference introduced whenoxidation and reduction occur simultaneously, separating the oxidationand reduction stages also results in improved, or more efficient,conversion. For some aromatic ring structured compounds, such asthiophene, it is difficult to reduce the compound because of the outerring structure of carbon elements, which tend to hinder hydrogen fromreacting with the sulfur element inside the ring structure. However, ifthese aromatic ring structured compounds are first oxidized before beingreduced, the oxygen reacts with the carbon elements to form CO₂ and SO₂,which permits a subsequent introduction of hydrogen in a reduction stageto react with the SO₂ to form H₂S. As a result, less coke is formed andmore sulfur is converted to H₂S. This is more particularly shown in thefollowing formulas.

[0056] Where C₄H₄S is thiophene.

[0057] It should be known that not all aromatic compounds require bothoxidation and reduction, as with thiopene, and that some aromaticcompounds may be oxidized or reduced to provide sufficient detection ofthe desired component. For example, for the detection of Nitrogen inpyridine, reduction is not needed to efficiently convert Nitrogen intonitrous oxide NO, which is detectable by sensor 52.

[0058] Conversely, for the detection of chlorine in methylene choride,oxidation is not needed to efficiently convert Chlorine intohydochloride HCl, which is detectable by sensor 52.

[0059] For detecting an amount of phosphine present in a phosphorouscomposition, reduction with hydrogen suffices to efficiently convert thephosphorous compound into phosphine, which is detectable by sensor 52.However, empirical testing shows increasing the temperature withinreactor 42 to 1200° C., as opposed to 1000° C. for sulfur, chlorine, ornitrogen measurements, facilitates reduction and, therefore, detectionof phosphine, whereas detection of sulfur, chlorine, or nitrogen is notneeded to be enhanced at this elevated temperature to facilitatedetection. In the alternative, and in some embodiments, placing sodiumborohydride within reactor 42 facilitates reduction of the phosphorouscompound at a reactor temperature of between approximately 600°-1000° C.The following formula illustrates the conversion from a phosphorouscompound to phosphine.

[0060] The more efficient the oxidation/reduction, the more likely theelectrons released during oxidation/reduction indicate the component tobe detected and the more accurate the concentration of the component isdetermined. A preferred range for oxidizing/reducing the component is toan efficiency of between approximately 90% and approximately 100%. Amore preferred range for oxidizing/reducing the component is betweenapproximately 95% and approximately 100%. An even more preferred rangefor oxidizing/reducing the component is between approximately 98% andapproximately 100%. The most preferred is to oxidize/reduce thecomponent to 100% or approximately 100% efficiency. As a result ofcomplete, or efficient, oxidation/reduction, the gas component isdetected more accurately than traditional detectors. Traditionaldetectors generally have detection capabilities in the ppm range, thatmerely oxidize or reduce or do so with a lesser efficiency, or not ascompletely, than reactor 30, which generally has detection capabilitiesin the ppb range.

[0061] It is understood that although reactant 34 and second reactant 46are described to be oxidative and reductive reactants, respectively, inother embodiments, reactant 34 may be reductive and second reactant maybe oxidative.

[0062] As shown in FIG. 5, electrochemical gas sensor 52 is placed at anoutlet 48 of second passage 44 for detecting a gas component in the gassample. Sensor 52 may be used with any of the reactors depicts in FIGS.2-4 having an outlet. Sensor 52 provides enhanced sensitivity overtraditional sensors and/or conductivity sensors, the disadvantages ofthese are mentioned above under the Background of the Invention, due tothe 3 way contact between the gas sample to be analyzed, sensingelectrode 56, and electrolytic material 58. The 3 way direct contactpermits the gas component in the gas sample to be detected withoutnecessitating the gas sample be substantially absorbed or diffusedthrough any electrolytic solution or membrane, thereby reducing thesensor response time and, without possible losses through absorption ordiffusion, sensitivity may also be enhanced.

[0063] Sensor 52 includes a substrate 62 having a surface 64 fordepositing electrodes thereon, an electrode 56 in contact with surface64, an ionomer membrane 58 in contact with surface 64 and electrode 56,ionomer membrane 58 having a first surface 66 and a second surface 68,and an opening 70 in ionomer membrane 58 extending from first surface 66to second surface 68 in a location proximate to electrode 56, therebydefining a passage for providing diffusion control for the gas.

[0064] In all of the embodiments shown in FIGS. 2-4, and for the purposeof detecting compounds having hydrogen, the presence of oxygen plays asignificant role in the oxidation and/or reduction of the gas sample. Ifthere is an insufficient amount of oxygen, oxidation/reduction may belimited, which inhibits a complete oxidation/reduction. An excess amountof oxygen will react with the hydrogen in the compound that is to bedetected and such a reaction may lead to the formation of condensation,which, in effect, absorbs the hydrogen in the compound that is to bedetected.

[0065] For the embodiments shown in FIGS. 2-4, for approximately every100 cm³ of H₂, the range of oxygen is preferably between approximately 1and 10 cm³. A more preferable range of oxygen per 100 cm³ of H₂ isbetween approximately 2 and 6 ft³. A preferred medium for providingoxygen is air because it is in a gas phase as opposed to a liquid phase.

[0066] The flow rate of reactants 34 and 36 are dependent upon the sizeof the gas sample, which may be expressed in volume, and chemicalcomposition of the organic compound. For example, referring to formula1, for sufficient oxidation of 1 ml of propylene, 4.5 ml/min of oxygenor its equivalent of 21.42 ml/min of air is needed. The saturated watervapor pressure at 25° C., above which undesirably leads to watercondensation, is 23.756 mm of mercury, which is 3.12% of atmosphericpressure (23.756 mmHg/760 mmHg×100=3.12%). According to formula 4.1 mlwater needs 0.5 ml of oxygen. Therefore, to avoid water condensation,which leads to h2s absorption and loss in signal at 25° C. and 1 atm,the oxygen content is ½ that of the saturated water vapor pressure, or1.56%, of the total reaction gas mixture. On this basis, and referringto formula 1, the hydrogen flow rate is either 64.10 (100/1.56) timesthe oxygen flow rate. Instead of oxygen, air may be used, in which casethe hydrogen flowrate is 13.46 times the flow rate of air.

[0067]FIG. 6 depicts a method 100 for providing a reactor, including thesteps of providing 118 a first reactant, providing 120 a secondreactant, and premixing 102 the first and second reactants together.Although only two reactants are shown to be premixed together, method100 may mix any number of reactants together.

[0068] Method 100 further includes the step of providing 122 a gassample and combining 104 the premix and gas sample together. Optionally,method 100 may also include the step of providing 106 a chamber andhomogeneously combining the premix and gas sample in the chamber. Methodalso heats 108 the premix and gas sample in, preferably, heater 42.Method further provides 116 an electrochemical gas sensor, in accordancewith the description of sensor 52, and detects 114 a gas component inthe gas sample.

[0069] Optionally, and for embodiments where oxidation and/or reductionmay be desired for facilitating detection 114 of the gas component,method 100 may include the step of reducing 110 the premix and gassample. In addition to, or instead of reducing 110 the premix and gassample, method 100 may also include oxidizing 112 the premix and gassample. Oxidation and/or reduction include all known or novel manners inthe art.

[0070] In another aspect of the invention, FIG. 7 depicts a method 130for providing a reactor, including the steps of providing 132 a firstreactant, providing 134 a gas sample, and mixing 136 the first reactantwith the gas sample. Optionally, method 130 may also include the step ofproviding a chamber and homogeneously mixing the first reactant and gassample together in the chamber.

[0071] Method further includes heating 138 the mixture of the firstreactant and gas sample in, preferably, heater 42. Method furtherprovides 140 a second reactant and heats 142 the first reactant, secondreactant, and gas sample together. Method 130 also provides 150 anelectrochemical gas sensor, in accordance with the description of sensor52, and detects 148 a gas component in the gas sample.

[0072] Optionally, and for embodiments where oxidation and/or reductionmay be desired for facilitating detection 148 of the gas component,method 130 may include the step of reducing 144 the mixture of the firstreactant, second reactant, and gas sample. In addition to, or instead ofreducing 144 the mixture of the first reactant, second reactant, and gassample, method 130 may also include oxidizing 146 the first reactant,second reactant, and gas sample. Oxidation and/or reduction include allknown or novel manners in the art.

[0073] Similar with method 100, although only two reactants are shown inFIG. 7, multiple reactants may be mixed 136 with the gas sample and/orheated 142 with the first reactant and gas sample.

[0074] The present invention, therefore, provides a

[0075] Although the invention has been described with reference to aparticular arrangements of parts, features and the like, these are notintended to exhaust all possible arrangements or features, and indeedmany other modifications and variations will be ascertainable to thoseof skill in the art.

What is claimed is:
 1. A reactor, comprising: a heater; a passage fortransporting a reactant; a chamber containing a gas sample and beingcoupled to said passage for receiving the reactant and mixing thereactant with the gas sample; a connector leading from said chamber tosaid heater for transporting a mixture of the reactant and gas sample;and wherein said heater heats the mixture of the reactant and gassample.
 2. The reactor according to claim 1, wherein said passagefurther includes a second reactant.
 3. The reactor according to claim 1,further comprising a second passage coupled to said connector fortransporting a second reactant to the mixture of the reactant and gassample.
 4. The reactor according to claim 3, wherein said connector isplaced within said second passage.
 5. The reactor according to claim 3,wherein said second passage is concentric with said connector.
 6. Thereactor according to claim 1, wherein said connector is coupled to anoutlet.
 7. The reactor according to claim 6, further comprising anelectrochemical gas sensor coupled to an outlet for detecting a gascomponent in the gas sample.
 8. The reactor according to claim 7,wherein said electrochemical gas sensor comprises a substrate having asubstrate, an electrode deposited on a surface of the substrate, anionomer membrane in contact with the surface and electrode, the ionomermembrane having a first surface and a second surface, and an opening inthe ionomer membrane extending from the first surface to the secondsurface in a location proximate to the electrode, thereby defining apassage for providing diffusion control for the gas.
 9. A reactor,comprising: a heater; a first passage for transporting a first reactant;a second passage for transporting a second reactant; a connectorcontaining a gas sample and being coupled to said first passage forreceiving the first reactant and mixing the first reactant with the gassample; said connector extending from said first passage through saidheater and coupling to said second passage for receiving the secondreactant and mixing the first reactant and gas sample with the secondreactant; and said second passage passing through said heater, wherebythe second reactant, first reactant, and gas sample are heated by saidheater.
 10. The reactor according to claim 9, further comprising anelectrochemical gas sensor coupled to said second passage for detectinga gas component in the gas sample.
 11. A method for providing a reactor,comprising the steps of: premixing at least two reactant gases together;combining the premix of the at least two reactant gases with a gassample; heating the premix and gas sample; and detecting a gas componentin the gas sample using an electrochemical gas sensor having asubstrate, an electrode deposited on a surface of the substrate, anionomer membrane in contact with the surface and electrode, the ionomermembrane having a first surface and a second surface, and an opening inthe ionomer membrane extending from the first surface to the secondsurface in a location proximate to the electrode, thereby defining apassage for providing diffusion control for the gas.
 12. The methodaccording to claim 11, further comprising the step of providing achamber and homogeneously combining the at least two reactant gases andgas sample in the chamber.
 13. The method according to claim 11, furthercomprising the step of oxidizing the premix and gas sample.
 14. Themethod according to claim 11, further comprising the step of reducingthe premix and gas sample.
 15. A method for providing a reactor,comprising the steps of: mixing a first reactant gas with a gas sample;heating the mixture of the first reactant gas with the gas sample priorto adding the second reactant gas, adding a second reactant gas to thefirst reactant gas and gas sample; heating the first reactant gas,second reactant gas, and gas sample; and detecting a gas component inthe gas sample using an electrochemical gas sensor having a substrate,an electrode deposited on a surface of the substrate, an ionomermembrane in contact with the surface and electrode, the ionomer membranehaving a first surface and a second surface, and an opening in theionomer membrane extending from the first surface to the second surfacein a location proximate to the electrode, thereby defining a passage forproviding diffusion control for the gas.
 16. The method according toclaim 15, further comprising the step of providing a chamber andhomogeneously combining the first reactant gas, second reactant gas, gassample, and combinations thereof in the chamber.
 17. The methodaccording to claim 15, further comprising the step of oxidizing thepremix and gas sample.
 18. The method according to claim 15, furthercomprising the step of reducing the premix and gas sample.